Three big power lines serving Southern California were back in operation Friday after a raging wildfire knocked them out of service Thursday, state energy officials said. But they cautioned that the fire, burning out of control some 30 miles (50 km) northeast of Los Angeles, still posed a threat to the local power grid. "The lines affected yesterday are back in service, but the fire is still burning. It's still a difficult situation to predict. We're still on the edge of our seats," California ISO spokesman Gregg Fishman said. The ISO operates most of the state's power grid. Thursday afternoon the fire, near Saugus, Calif., raced through the brush under the DC Intertie, shutting the 500 kilovolt line that links Southern California with the giant hydroelectric dams up on the Columbia River. Soot from the fire also short circuited lines on the nearby Path 26 corridor that connects the Southern California Edison power grid with that of Pacific Gas & Electric in Northern California. At one point Thursday SoCal Edison warned that the loss of the lines might force them to cut power to some industrial customers to balance the load on the grid, which was already straining to keep up with heavy air conditioning demand. "The good news is that it is cooler today. Loads should be lower. We had enough resources yesterday to deal with a situation that was much more serious than it's likely to be today," Fishman said. Officials at the Los Angeles Department of Water and Power said the DC Intertie line was shut Thursday around 1:30 p.m. Pacific time and switched back on at 2 a.m. Friday. The line's capacity has not been affected by the fire and it will likely be carrying around 2,900 megawatts later Friday, LADWP assistant general manager Henry Martinez told Reuters. Tom Boyd, a spokesman for SoCal Edison, said the utility lost two 500 kilovolt lines Thursday but both were back in service by 10:53 p.m. "As long as the lines hold up we shouldn't have any problems supplying power. Hopefully it will be business as usual (today)," Boyd said.